m3_lightmeter/lib/screens/settings/components/shared/dialog_range_picker/widget_dialog_picker_range.dart

import 'package:flutter/material.dart';
import 'package:lightmeter/generated/l10n.dart';
import 'package:lightmeter/res/dimens.dart';
import 'package:m3_lightmeter_resources/m3_lightmeter_resources.dart';

class DialogRangePicker<T extends PhotographyValue> extends StatefulWidget {
  final Icon icon;
  final String title;
  final String description;
  final List<T> values;
  final List<T> selectedValues;
  final String Function(BuildContext context, T value) valueAdapter;

  const DialogRangePicker({
    required this.icon,
    required this.title,
    required this.description,
    required this.values,
    required this.selectedValues,
    required this.valueAdapter,
    super.key,
  });

  @override
  State<DialogRangePicker<T>> createState() => _DialogRangePickerState<T>();
}

class _DialogRangePickerState<T extends PhotographyValue> extends State<DialogRangePicker<T>> {
  late int _start = widget.values.indexWhere((e) => e.value == widget.selectedValues.first.value);
  late int _end = widget.values.indexWhere((e) => e.value == widget.selectedValues.last.value);

  @override
  Widget build(BuildContext context) {
    return AlertDialog(
      icon: widget.icon,
      titlePadding: Dimens.dialogIconTitlePadding,
      title: Text(widget.title),
      contentPadding: EdgeInsets.zero,
      content: SizedBox(
        width: double.maxFinite,
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            Padding(
              padding: Dimens.dialogIconTitlePadding,
              child: Text(widget.description),
            ),
            Padding(
              padding: const EdgeInsets.symmetric(horizontal: Dimens.paddingL),
              child: DefaultTextStyle(
                style: Theme.of(context).textTheme.bodyLarge!,
                child: Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: [
                    Text(widget.valueAdapter(context, widget.values[_start])),
                    Text(widget.valueAdapter(context, widget.values[_end])),
                  ],
                ),
              ),
            ),
            Row(
              children: [
                Expanded(
                  child: RangeSlider(
                    values: RangeValues(
                      _start.toDouble(),
                      _end.toDouble(),
                    ),
                    max: widget.values.length.toDouble() - 1,
                    divisions: widget.values.length - 1,
                    onChanged: (value) {
                      setState(() {
                        _start = value.start.round();
                        _end = value.end.round();
                      });
                    },
                  ),
                ),
              ],
            ),
          ],
        ),
      ),
      actionsPadding: Dimens.dialogActionsPadding,
      actions: [
        TextButton(
          onPressed: Navigator.of(context).pop,
          child: Text(S.of(context).cancel),
        ),
        TextButton(
          onPressed: () => Navigator.of(context).pop(widget.values.sublist(_start, _end + 1)),
          child: Text(S.of(context).save),
        ),
      ],
    );
  }
}